1. Field of the Invention
The present invention relates to a current control apparatus, and more particularly, to a current control apparatus that can be applied to a bipolar junction transistor (BJT) to prevent temperature measurement errors from occurring when using a dual current mode temperature measurement method to measure the temperature of the BJT.
2. Description of the Prior Art
Please refer to FIG. 1. FIG. 1 shows a simplified diagram of a bipolar junction transistor (BJT) 100 in accordance with prior art. As shown in FIG. 1, the BJT 100 has a base terminal, an emitter terminal, and a collector terminal. The base current Ib, the emitter current Ie, and the collector current Ic of the BJT 100 have the following connections:Ib+Ie+Ic=0Ie=−(β+1)Ic/β
In addition, a person of average skill in the pertinent art of the BJT should be able to understand about how to use a dual current mode temperature measurement method to measure the temperature of the BJT 100. The dual current mode temperature measurement method measures an emitter current Ie1 and another emitter current Ie2 of the BJT 100 at different times and calculates a temperature measurement result accordingly. However, since the temperature of the BJT is related to a ratio between a collector current Ic1 and another collector current Ic2, when β value of the BJT 100 becomes smaller in the advanced process and varies according to the current variation, the above temperature measurement method is unable to obtain the actual ratio between a collector current Ic1 and another collector current Ic2. Thus, the above condition will result in serious temperature measurement errors.